The selection and installation tips for metal tube float flow meter

Author:Source:Date: 2018-05-17 17:20:17

Metal tube float flow meter is a type of
variable area flowmeter. In a vertical conical tube that expands from bottom to
top, the gravity of a float with a circular cross section is absorbed by the
liquid, and the float can rise freely in the cone. And drop. Under the action
of flow velocity and buoyancy, it moves up and down. After balancing with the
weight of the float, it is transmitted to the dial through the magnetic
coupling to indicate the flow. Generally divided into glass and metal rotor
flowmeter. The metal rotor flowmeter is the most commonly used in the industry.
For small diameter corrosive media, glass is usually used. Due to the inherent
fragility of the glass material, the key control point also uses a rotameter
made of precious metals such as full titanium. . Mainly used in petroleum,
chemical, power generation, pharmaceutical, food, water treatment and other
complex, harsh environmental conditions, and various media conditions in the
flow measurement process.

Selection tips

1. For the selection of remote transmission
type metal rotor flowmeter, it is necessary to select the flowmeter suitable
for the type of explosion-proof required in the place of use; the installation
should also pay attention to the fastening of the case and the sealing of the
wiring port after the power is supplied to the instrument, which has reached
the explosion-proof, protection, and prevention Erosion requirements.

2. For places where the temperature of the
measured medium is too high (>220°C) or too low, it is usually necessary to
take insulation or heat insulation measures on the sensor part of the flow
meter to ensure that the signal converter ------ indicator works properly. The
ambient temperature should be selected high temperature indicator.

3. For some need to take insulation or
cooling of the measured media, choose jacket type flowmeter.

4. For the pressure of the flowmeter inlet
media instability, especially for gas measurement, in order to ensure accuracy
and service life, damping structure should be selected.

5. For the medium requires a higher-pressure
level, more than the standard pressure level, select the high-pressure type
structure in the selection, high pressure type using HG20595-97 RF with neck
butt welding steel pipe flange.

6. Metal rotor flowmeter measurement
accuracy is generally 2.5, when the required measurement accuracy is higher,
the metal rotor flowmeter should not be selected.

Installation tips

1. Before installation, the ejector rods,
fillers, rubber bands, etc. used for the protection of the flowmeter should be
taken out, so that the float can be changed to a certain position and the state
of operation of the converter can be checked. If it is considered abnormal, it
should be adjusted.

2. The flowmeter should be installed
vertically on the non-vibrating pipeline. The inclination of the measuring tube
should be less than 5°, and bypass should be installed to facilitate
maintenance and cleaning without affecting production.

3. When the flow meter is installed, the
level meter should be strictly calibrated, and the assembly should not be
stressed. The flow direction of the vertical installation type rotor flowmeter
is from bottom to top, and the flow direction of the horizontal installation
type rotor flowmeter should be consistent with the marking direction. For ease
of use and dismantling, valve assemblies are generally required.

4. The remote transmission metal
flowmeter's remote transmission part is magnetically coupled to the rotor. If
the medium contains small particles that are easily adsorbed by magnetic substances,
the rotor is easily worn out and jammed, resulting in inaccurate or
unmeasurable measurements. The solution is to install a magnetic filter in
front of it.

5. In the upstream of the flowmeter should
install the valve, in the downstream 5 to 10 times the instrument diameter
installed flow control valve.

6. The instrument does not have a strict
upstream straight pipe length requirements.